The present invention relates to a lift bed.
EP-B1-0 418 415 discloses a suspended bed with a vertically adjustable bed frame and a lifting device for moving the bed frame in the vertical direction. The suspended bed comprises a vertically extending guide means which is secured to the wall and on which one end face of the bed frame is supported such that it is movable in the vertical direction. The lifting device is provided with a self-locking drive and it is implemented and arranged in such a way that it acts on the above-mentioned end face of the bed frame.
The lifting device is provided with at least one electric motor for driving self-locking lifting spindles, a crank being provided for emergency operation; this crank is adapted to be coupled to the lifting spindles and it is in mesh therewith when the crank is rotated.
The suspended bed described in EP-B1-0 418 415 takes up very little space and it is safe in operation. In particular, if the lifting device is arranged in the area of the guide means, practically no floor space is occupied, when the suspended bed has been raised to the position below the ceiling. In addition, the self-locking drive permits the suspended bed to be supported reliably and vibration-free at any vertical position.
Starting from the known prior art, it is the object of the present invention to provide a lift bed which offers higher operational comfort.
The present object is, in particular, achieved by a lift bed comprising a vertically adjustable bed frame and a pulling device for moving said bed frame in the vertical direction, said lift bed comprising two carriages which are secured to an end face of the bed frame such that they are horizontally spaced from one another, each of said carriages being supported such that it is movable on a vertical guide rail by means of rollers, said two carriages being each connected via a pull chain or a toothed belt to a counterweight; each pull chain or each toothed belt is guided over a drive wheel at the upper end of the respective guide rail; the drive wheels are rigidly coupled via a coupler rod; the coupler rod is connected to a main reel which is arranged in vertically spaced relationship with a counterreel; the main reel and the counterreel are interconnected by a drive belt, said drive belt being used for rotatably driving the coupler rod; and the counterreel is adapted to be driven selectively in one direction or the other by means of a motor coupled to a reduction gearing and used for rotating the coupler rod.
The present invention is based on the finding that the lift bed disclosed is very easy to operate and, in particular, that it makes extremely little noise when in operation. In addition, a suitable structural design of the counterweights according to the present invention permits the use of an energy-saving motor.
The preferred embodiment has the advantage that the main reel and the counterreel can be installed in a countersunk mode and that the part of the drive belt extending between said main reel and said counterreel can, via respective guide means, be attached such that it is freely accessible for possible operation by hand. It follows that, e.g. in the case of power failure, the lift bed can be moved manually from one vertical position to another and will therefore be operable in any case.
A further development has the advantage that the drive motor is implemented as a tube motor and can therefore be arranged e.g. in the interior of the counterreel. The counterreel and the drive motor can be combined in a space-saving manner in this way.
Still another development has the advantage that the motor coupled to the reduction gearing is implemented as a self-locking component.
Another development has the advantage that the motor is implemented such that its rated power does not exceed 100W, i.e. it operates in an energy-saving mode.
A further development has the advantage that the carriages are each bipartite, each part comprising at least one roller and the two parts of a carriage being interconnected in such a way that one part is adapted to be tilted relative to the other part about a horizontal axis extending parallel to the coupler rod.
A further development has the advantage that each carriage is provided with an adjusting device by means of which the two parts can be adjusted relative to one another. Hence, the bed can easily be oriented horizontally, i.e. parallel to the floor, by adjusting the carriages in a suitable manner.
A further development has the advantage that the mass of the counterweight exceeds that of the bed frame. The bed frame can therefore be moved vertically upwards without any necessity of driving the coupler rod by the drive motor or by a user by means of the drive belt.
Another development has the advantage that the mass of the counterweight is less than that of the bed frame so that, when the coupler rod is released, the bed frame will move automatically downwards in the vertical direction.